Pressure gauge adjusting device



July 30, 1940. G. F. RUOPP PRESSURE GAUGE ADJUSTING DEVICE Filed May 20, 1938 Patented July 30, 1940 UNITED STATES 2,209,540 PRESSURE GAUGE ADL'IUSTING DEVICE Gcorge Frederick Ruopp,

Marshalltown, Iowa,

assignor to MarshalltownManufacturing Com- Dany, Marshalltown, Iowa.

Iowa, a corporation of Application May 20, 19a; "Sim-i1 No. 209,046

1 Claim.

This invention relates to pressure gauges of the Bourdon tube variety and especially gauges for recording the higher pressures.

It is well known to gauge manufacturers that 5 during the manufacture and assembly of these gauges, variations occur in the several parts so that when assembled and tested under pressure it frequently occurs that the indicator hand-does not accurately register with the scale printed upon the dial, and manufacturers generally provide some means for making such readjustments. However, when such accurately adjusted gauges are shipped, handled and installed, and after continued use, it frequently happens that the indicator hand does not accurately register with the dial.

The object of my invention is to provide simple, durable and inexpensive means whereby an unskilled operator may readily, quickly and accurately readjust the indicator hand relative to the dial without in any manner decreasing the accuracy of the gauge after such readjustment.

In the accompanying drawing Figure 1 shows a vertical central sectional view of the gauge casing having my improved gauge therein;

Figure 2 shows a front elevation of same with the gauge front removed;

Figure 3 shows a detail side view-of the indicator hand-operating mechanism taken on the line 3-3 of Figure 2;

Figure 4 shows an enlarged detail view, partly in section, showing the expansible link;

Figure 5 is the rear elevation of same; and

Figure 6 shows a sectional view on the line 6-6 35 of Figure 5.

My invention is intended for use in connection with pressure gauges of the kind employing Bourdon tubes, and these gauges customarily have a casing ill, with a detachable glass front II and a detachable metal plate l2 spaced rearwardly from the glass front, and a Bourdon tube fixed to one end of the stationary member Id, at the end of which the fluid under pressure to be gauged is admitted in the ordinary manner not shown.

For the purpose of visually recording pressure within the Bourdon tube these gauges customarily are equipped with a rotatable shaft I5 to which the indicating hand [6 is fixed. On the shaft I5 is a pinion l1 and the usual hair spring [8.

For actuating the pinion I! there is usually provided a lever l9, pivotally supported at 2B and having a sector 2| in mesh with the pinion l1.

5 Slidingly mounted upon the lever I9 is a lever member 20 having a slot 22 to receive the set screw 23 for adjustably securing the parts I9 and 2| together.

For the purpose of connecting the Bourdon tube with the sector H I have provided a device comprising a link member 24 and a link member 25, the latter being provided with side members 26t0 engage the edges of the link member 25 and permit longitudinal movement of the links and to prevent lateral movement of the links relative to each other. In the link 24 I have mounted a rotatable shaft 21, and on this shaft is an eccentric 28, and on the eccentric is a slotted screw-head 29. The eccentric 28 is rotatably mounted within a suitable opening formed in the link member 25, and the screw head 29 preferably is extended through an opening 3|] in the plate l2, as shown in Figure 1, so as to be readily accessible to an operator upon removal of the glass front only.

For the purpose of holding the link members 24 and 25 in their various positions of adjustment relative to each other I have provided the screws 3| seated in the link 24 and extended through slots 32 in the link member 25, with washers 33 on said screws.

In practice it is well known that where these result that upon testing the assembled gauges it is frequently necessary to readjust the position of the indicator hand relative to the zero mark on the gauge. This is frequently done after such testing by mechanism such as the adjustable member 20 of the sector lever 19, and this is usually done during the assembling and by skilled operators.

In practice I have found that during shipment, handling and installation, and also after extensive use, it frequently occurs that the position of the indicating hand relative to the gauge scale is not at the zero mark where no pressure is applied to the gauge, hence, all of the readings on the gauge are correspondingly inaccurate. I have demonstrated in practice that with my improvement, and in the event of the inaccurate adjustment of the indicating hand, an unskilled operator may readily and easily remove the glass front of the gauge, and with an ordinary screw driver adjust the eccentric to thereby lengthen or shorten the link, and thereby bring the in dicator hand to the zero mark, after which the readings on the gauge will be just as accurate throughout its entire range as when originally constructed.

I have found also in actual practice that when the two parts of the link are originally assembled and installed they Will hold the link members against any such sliding movements relative to each other as are likely to occur in practice, and

I claim as my invention:

An adjustable link, comprising a link member having a bearing opening therein, a second link member resting upon the first link member and formed with a longitudinally arranged slot, a

screw passed through said slot and seated in the first link member for frictionally holding the two link members together against normal pressures and permitting one to slide longitudinally relative to the other when excessive pressure is applied, and an eccentric within said bearing opening and rotatab-ly mounted in the second link member, whereby a rotation of the eccentric will either lengthen or shorten the link, which may be done without adjustment of said screw.

GEORGE FREDERICK RUOPP. 

